1. Field of the Invention
The present invention relates to an adjustable nozzle assembly for mounting to a trigger sprayer which is used in dispensing liquids and more particularly to an assembly for dispensing liquid in a spray or jet mode and for containing the liquid in an off mode.
2. Description of the related art including information disclosed under 37 CFR .sctn..sctn. 1.97-1.99
A variety of simple and inexpensive hand-operated pumps for use as dispensers of liquid have been developed which include means for coupling to a container from which a liquid is to be dispensed under pressure. Such a dispenser typically includes a trigger which is intended to be moved manually to operate a pump piston within a cylinder in a body of the dispenser, usually against the force of a return spring, so that liquid may be pumped from the container and dispensed through an ejection nozzle or outlet orifice.
To meet consumer demands for convenience it has been found highly desirable that the nozzle be adjustable to provide widely varying discharge patterns such as a spray pattern and a stream pattern. It is further preferable that the nozzle assembly not only be adjustable to accommodate a stream or spray mode of operation in a highly reliable fashion, but that it also conveniently engage into an off mode position to contain the liquid in the dispenser to prevent leakage or inadvertent discharge of the liquid and to promote easy storage of the container of liquid by the ultimate consumer.
To minimize cost, the various parts of the prior art dispensers are increasingly made of plastic resins suitable for injection molding. Further, it has been found to be highly desirable that the design of the dispenser be increasingly simplified such that the number of separately molded parts are minimized and so that the assembly of the parts may be mechanized at minimum cost and with maximum economy.
Heretofore, various designs or configurations of nozzle assemblies have been proposed to accommodate the above referenced desirable features, particularly the feature that the nozzle assembly be adjustable to provide widely varying discharge patterns, i.e. a spray pattern and a stream pattern.
Examples of prior dispensers, including adjustable nozzle cap assemblies for selectively dispensing a liquid in spray or stream mode, are disclosed in the following U.S. patents:
______________________________________ U.S. Pat. No. PATENTEE ______________________________________ 4,767,060 Shay et al. 4,706,888 Dobbs 4,247,048 Hayes 4,234,128 Quinn et al. 3,843,030 Micallef ______________________________________
In U.S. Pat. No. 4,767,060 there is disclosed a nozzle assembly which is capable of selectively dispensing a liquid product as a foam or a spray by means of a selectively movable member to establish a swirl chamber located in between and in liquid communication with a passageway and a nozzle outlet orifice. Such member can be moved forward into the nozzle cap where it offers no interference with the vortical liquid sheet to effect a spray mode of delivery. The member can be moved rearwardly to a point where the swirl chamber interferes with the vortical sheet to produce a stream pattern. Gas passageways are provided in this structure to achieve aeration of the turbulent fluid and the resultant dispensing of the liquid as a foam.
In U.S. Pat. No. 4,706,888 there is disclosed a nozzle assembly capable of being opened and closed in selective rotative positions of a nozzle cap of the assembly with respect to two discreet passageways formed between a discharge conduit and a discharge orifice to provide an alternating off, stream and spray position for a liquid dispenser. Such multiple passages in a cylinder and the nozzle cap cooperate to move in and out of alignment and communication thus providing the spray and stream mode of operations depending upon alignment and registry of the various described passages and grooves. U.S. Pat. No. 4,706,888 alleges the following drawbacks in the devices disclosed in U.S. Pat. Nos. 3,843,030 and 4,234,128:
"For example, U.S. Pat. No. 3,843,030 has its nozzle cap containing an off-centered discharge orifice which must be shifted upon cap rotation between alignment with the spin chamber at the end of an internal probe for producing a spray, and a channel on the probe for producing a stream. The off center location of the discharge orifice not only presents problems for the consumer in properly targeting the discharge, but gives rise to a shearing action during cap rotation in that the inner edge of the discharge orifice must traverse the plug surface containing the spin chamber and associated tangentials which could cause abrasions or snags between the rotating parts resulting in undue wear and leakage . . . The nozzle assembly of U.S. Pat. No. 4,234,128 like-wise requires the spin chamber and associated tangential grooves to be formed on the underside of the cap end wall, and passages and slots on an internal plug arranged to produce a stream or spray discharge or shut-off. Thus, some of the details for the dispense function are on the cap end wall and some others are on the plug confronting this end wall, such that a shearing action results between these details as they pass one another upon cap rotation. Due to such abrasive and interrupted engagement between rotating parts, scoring, snags and/or undue wear occurs with consequent leakage."
With respect to U.S. Pat. No. 3,843,030 it is observed that the tubular extension described therein includes a free end having a staggered recess for cooperation with the cap in producing spray and stream modes of operation.
In U.S. Pat. No. 4,247,048 there is disclosed a two-piece nozzle assembly which features a tubular member having a circular, planar face at its terminal end with a recess in the planar face. When a cap is rotatably mounted to the tubular member it has an end wall with a planar inside surface which will form an interface with the circular planar face of the tubular member. The dispensing orifice of the cap is radially displaced from the center axis of the cap which is registerable when properly aligned with the recess of the planar face.